imaq1394ConfigEventMessage
Format
rval = imaq1394ConfigEventMessage (SESSION_ID sessionID, int event, GUIHNDL windowHandle, int windowsMessageNumber, void *parameter);
Purpose
Configures the NI-IMAQ for IEEE 1394 Cameras driver to send a message to your application window when an event occurs. You must first register a callback function on a Windows message. The function you use to register the callback returns a Windows message used by the driver to notify your application. For more information, refer to the RegisterWinMsgCallback function in the following LabWindows/CVI menu: Library»User Interface»Callback Functions»Windows Interrupt Support.
In the callback function, the wParam parameter contains the event that sent the message. To send a message to the main thread, pass the window handle returned by GetCVIWindowHandle. To send a message to another thread, you must have created at least one top-level panel in that thread. Pass the window handle for that panel to imaq1394ConfigEventMessage. You can obtain the window handle for the top-level panel by calling GetPanelAttribute with the ATTR_SYSTEM_WINDOW_HANDLE attribute.
Parameters
Parameter | Type | Description |
sessionId | SESSION_ID | A valid Session ID, which you can obtain using imaq1394CameraOpen2. |
event | int | The event to monitor. The following events are valid:
FRAME_DONE CAMERA_ATTACHED CAMERA_DETACHED |
windowHandle | GUIHNDL | The handle of the window that receives messages from the NI-IMAQ for IEEE 1394 Cameras driver. Use the following functions to get the handle:
|
windowsMessageNumber | int | The Windows message number returned by RegisterWinMsgCallback. |
parameter | void * | A pointer to user-defined data passed to the event function. |
Return Value
On success, this function returns IMG1394_ERR_GOOD. On failure, this function returns an error code. You can obtain a more detailed error message with imaq1394ShowError.